Hello all,

I joined these forums about a year or so ago as I entered the world of Mazda and the rotory! Over the past year I have been frugal purchasing random parts from many of you as I gathered all the needed parts to build our RX8 racecar. Two weeks ago I was at the LRP race, I took all my crew guys out on a "Date" to thank the for everything they have done on the car. At the event I met several forum members so I figured that I should share some pictures to show you what we have been up to! WE took this car down to the bare shell, not one wire or bolt was left on it. We have painted and or cleaned every part and it really is coming along great! This past weekend was a big weekend for us as we installed the engine, drivetrain, radiator, and the suspension. Hopefully this weekend we will have it running (Provided a few last minute parts come in!) I want to thank everyone that sold me stuff dirt cheap to make this project come together! Our hopes are to have it on track at a test day on July 8th at New Hampshire Motor Speedway. If anyone wants to come up feel free to, I think the track charges ten bucks to get in. I will come back here and update this thread when we get it running and I'll share some more pictures soon!

Stephen Blethen
RST Performance Racing
www.RSTPerformance.com (Old site not currently updated)

We do have a facebook page that we have fun with and post pictures and updates. feel free to "like" us and make any comments you wish. It is in the professional sports team groups listed as "RST Performance Racing"

 

Just a quick shout out to a few members that gave me some smokin deals!

Berg Racing
Zelse
Baez
RX8
Sri
Figs
ebb
Works Concepts

OK group hug is over! Seriously though... thank-you!

Stephen

 

You definitely want these things:

-Start with new front hubs and ABS lines all the way around. The primary ABS failure are the sensors in the front hubs and the worst racing issue I've ever, ever encountered is this failure of one of the fronts. Basically they will read a bogus high value, the abs system reads this as not locked and one of the fronts will lock. Wherever your pointed is where you will go/hit. Daytona into the bus stop at 125. NOT a confidence builder.

-Get the MSpeed brake ducts as made by SpeedSource. You'll double or triple your brake pad life. The stock braking system is fine but with a DOT R or slicks the front calipers will flex and open giving you uneven pad wear. Depending how long you plan on keeping the car you can fix this with aftermarket front brakes. I have tested with tons of data two different piston sized StopTech ST-40's and in the long run they provide benefits---some of them hard to measure such as lowered hub temps due to aluminum hats and floating rotors. Expensive but once again WHEN you have that ABS brake failure the cost of the brakes are nothing to putting on a front clip.

-Contrary to popular belief, the car has better geometry when you run it higher.

-Same for standing up the tires.

-Get a front lower control arm inside offset bushing for more camber. You will need this. Mazdaspeed sells one.

-The weak link in the suspension for side to side contact is the smallest rear control arm. Get spares. Light contact will bend this rascal and you'll get instant toe changes.

-Fix your fuel delivery method by whatever method you find. Fuel slosh/fuel starve in these things turn to lean. Lean at 1,600 degree EGT's = boom.

-The weak link in the engine is the side seal springs.

-Get a fuel pressure gauge and watch it like a Hawk.

-Bag the old trans. The newer one will last forever

-You do want a very light flywheel and clutch pack. The ACT is a heavy boat anchor. The best aftermarket clutches weigh 3 times what we have run. Our entire flywheel and clutch pack assembly is lighter than the best clutch you can find. PM me and I'll give you the skinny. Under 2 grand in total.

-I have a radiator source if your racing style is to push people around/stay in the draft. The stock oil coolers are not bad but they are small.

-The 09+ fuel tank is about a gallon larger but 3/4" lower.

-Almost forget. You'll absolutely need a diff cooler. Absolutely. You'll see 300F without one with your exhaust running right past the diff.

 

Get that stock air box, battery and radiator bottle out of there to improve air flow. Open up the fender liners behind the oil coolers to improve air flow and better yet go with 12an line and thicker oil coolers while your at it.

Eric: I always take notes when you post, so I would like some clarification on your camber/ standing up the tires comment, it sounds contradictory. I thought we like 3+ deg neg in the front .5-1deg less in the rear?

 

In Improved Touring ABS must be disabled, the stock flywheel must be retained, and there is no allowance for a diff cooler.

 

There is no allowance for a battery change or relocation in ITR.

 

That sucks. Well find the smaller sized battery mazda offered. I think the weight difference was about 10lbs.

 

Cool build. Have you considered changing to STU or EP?

We are building a Mazda for STU right now, and the cool thing is its only a wheel/tire change and about 60lbs of ballast to run the same car in EP. Engine rules are very similar from ITR/STU/EP, but you get to address a lot of the other stuff. In STU you can keep the ABS, but get the lightened flywheel, remote reservoir shocks and the car will have a lower minimum weight. Best of all, STU and EP are National classes.

 

No ABS and stock flywheel but they can run a header? Or is the picture not accurate?

 

That is correct, the exhaust is open. The IT category is for old cars, you cant event get your car classed in IT until it is 5 years old. The idea is to give the cars that have aged out of Showroom Stock or Touring a place to play. The class was never intended for new technology, and they don't want to make the modern cars the front runners.

imho the best class for an RX-8 in Club Racing right now is EP. In Touring 3 you get run over by everything, no chance of keeping up with the S2K or Z's. In STU you might have a chance, while the 8 is way down on power for the class it is nice and light, so the car should be good over the long run. In EP you get to fix all of the shortcomings of the car, but the limited prep rules keep the engine build and suspension cost in check. You get to run real racing slicks and the car is actually competitive.

We considered an EP build with our car before we sold it, judging by the couple that are out there it looks like a blast. But with the Toyota ride looking to go till the end of 2012 I did not need another project.

 

WOW Lots of great replies and conversation!

Those rules issues everyone mentioned are accurate and something I do know about. I have been racing in IT for 11 years along with my twin brother and my dad has been running in IT for 27years... yup since the first year it started here in the northeast! I still value the feedback and appreciate you pointing that stuff out, I always welcome that type of feedback!

I did pick ITR because IT is close to my heart... been around it a long time! And because I think that Driving impressions has done an excellent job with the PRO-IT series here in the northeast. (www.proitseries.com) I do appreciate the suggestions but honestly STU really isn't for me. I know Greg very well (who is on the advisory comittee that I am sure ULLLOSE may know from the "sandbox") and he is really trying to push those ST classes to get them national BUT for me the depth of competition just doesn't exist. Same with EP for our area. The only highly attended races for the folks that run anything in production around here are the june sprints and runnoffs. Both of which are far to much of a travel and expense to run for me. Thanks for the ideas and I do agree the car would probably be better, certainly faster and more exciting to drive, but I am driving the car to race not lap I say that in the nicest way... don't take offense! PS to ULLOSE I am very jeliious of the toyato deal you have!

-Start with new front hubs and ABS lines all the way around. The primary ABS failure are the sensors in the front hubs and the worst racing issue I've ever, ever encountered is this failure of one of the fronts. Basically they will read a bogus high value, the abs system reads this as not locked and one of the fronts will lock. Wherever your pointed is where you will go/hit. Daytona into the bus stop at 125. NOT a confidence builder.
Thanks for this advice! Do you think the front hubs are a weak link? how often do you replace them?

-Get the MSpeed brake ducts as made by SpeedSource. You'll double or triple your brake pad life. The stock braking system is fine but with a DOT R or slicks the front calipers will flex and open giving you uneven pad wear. Depending how long you plan on keeping the car you can fix this with aftermarket front brakes. I have tested with tons of data two different piston sized StopTech ST-40's and in the long run they provide benefits---some of them hard to measure such as lowered hub temps due to aluminum hats and floating rotors. Expensive but once again WHEN you have that ABS brake failure the cost of the brakes are nothing to putting on a front clip.
Sadly stock brakes are per the rules... definetly running cooling. I have the part from **** racing that connects to the spindle... do you think that will work?


-Contrary to popular belief, the car has better geometry when you run it higher.
For this season I have the JIC coilovers... I know I know not great! But it will get the car on track! If anyone runs across some old Konis that need to be rebuilt let me know! (Eric... My 7 month old daughter was in the facebook picture that you commented on a few weeks ago, glad it made your week!)

-Same for standing up the tires.
Rears I assume?


-Get a front lower control arm inside offset bushing for more camber. You will need this. Mazdaspeed sells one.
I am curious what you are running? I know grand-am limits it to -3 but not sure on WC. Feel free to PM me or e-mail me any secrects for LRP, WG, Ohio, VIR, Summit and Jersey!

-The weak link in the suspension for side to side contact is the smallest rear control arm. Get spares. Light contact will bend this rascal and you'll get instant toe changes.
Just like the BMWs! Got it and will do... this is more great advise!

-Fix your fuel delivery method by whatever method you find. Fuel slosh/fuel starve in these things turn to lean. Lean at 1,600 degree EGT's = boom.
I have the tank from Johns continental car that got totalled at Daytona. I think it has a copy of the speedsource design, if not it is the speedsource pump.

-The weak link in the engine is the side seal springs.
So as I said I am new to the rotary... anyway to check on these or just wait until I am down on power and rebuild?

-Get a fuel pressure gauge and watch it like a Hawk.
Didn't think I needed this... what should I be looking for and why? is this to deal with the lean issue and not getting enough fuel?

-Bag the old trans. The newer one will last forever
Legal in 2014 when the 2009 model gets classed...per the update backdate rules. For now I gota try and make my three rebuilt 04 trannies make it... I am guessing I will get at least a DNF or two

-You do want a very light flywheel and clutch pack. The ACT is a heavy boat anchor. The best aftermarket clutches weigh 3 times what we have run. Our entire flywheel and clutch pack assembly is lighter than the best clutch you can find. PM me and I'll give you the skinny. Under 2 grand in total.
Clutches are free, flywheels are not. Will your clutch work without the flywheel your speaking of?

-I have a radiator source if your racing style is to push people around/stay in the draft. The stock oil coolers are not bad but they are small.
Running the Ron Davis. I have 1 with a spare in the trailer. Do you think I will be fine with that?

-The 09+ fuel tank is about a gallon larger but 3/4" lower.
Great info! This will be very handy in 2014 when I can update/backdate! Let me know when you strip a car and have one laying around!

-Almost forget. You'll absolutely need a diff cooler. Absolutely. You'll see 300F without one with your exhaust running right past the diff.
I am running the 5.12 diff so I am definetly concerned about heat. I am going to run a temp gauge to watch the tempature. What temps do you think it can run without coming apart? Races are 45 min in length.


Well find the smaller sized battery mazda offered. I think the weight difference was about 10lbs.
Was it offered in the RX8? if so what year?

Get that stock air box, battery and radiator bottle out of there to improve air flow. Open up the fender liners behind the oil coolers to improve air flow and better yet go with 12an line and thicker oil coolers while your at it.
Running an AEM since it was the closest to the mazdaspeed I could find... thoughts?
Fender liners are removed completly. Do you think I should run them in the rear?
Coolers and lines are free so I could modify those... Any suggestions?


Thanks for all your interest, support and ideas! I have been racing a while but mostly Audi/Ford, none of this rotary stuff! Keep the ideas and constructive critisism coming

Stephen Blethen

 

Subscribed.

Stephen, was great to link up with you for even the brief chat at LRP. Definitely will be watching your progress, and tagged you on FB.

(Mike, white RX-8 guy you have met a few times)

 

Which Ron Davis radiator? They have the one they make for Mazdaspeed which is ok at best. Then they have the "special" dual pass radiator they can make for you if you custom order it direct from Ron Davis... they'll know what you're talking about, ask for the "Mother's Special RX-8 Radiator" - it rocks!

 

Awesome build. Going to follow this.
As for the battery, I believe they are referring to the original 04 cars. In 05 Mazda issued a TSB and upgraded the cars to a faster/more powerful starter and a larger higher capacity battery to go with it.

I actually have the 05+ starter and original 04 battery in my 04 street RX8.

 

very cool to see one of these being built

I have a feeling I might be racing an RX8 once the MR2 meets its demise (hopefully not any time soon though!)

 

For the battery, I didn't join up until 07 and by then mazda put a larger battery in the car. I believe the 04's came with the smaller battery. Not sure if Mazda did a recall and installed larger batteries or if they just started using larger batteries.

AEM intake AKA Mazdaspeed. IMHO is the best choice. Some people have recommended modifing it so the filter is vertical instead of horizontal. Basicly cut off the last bend and turn it??? I am not 100% sure but I am sure you can figure it out.

No fender liners are probably best, I would just use something to shield the coolers form debris. Maybe mesh.

For Oil Cooler recommendations: Any race quality cooler, 12AN lines, no thermostat or a real thermostat and something thicker should do the trick. Of course the key is to maximize the air flow. If your running the stock bumper the cooler vents are small so sealing off any leaks is important.

While on the subject of the stock grill. You can probably get that plastic POS out of the way and just use some mesh. While your at it, you could ditch the stock crash bar and custom fab something smaller and lighter that is up and out of the way. That would improve air flow to the radiator.

 

Hubs: Yes they are a weak link. The higher the loads you expose to the hubs with tire choice, tracks, cooling and driving style the more you should replace them. We have had two FL wheel bearing failures in 5 years with 5 different cars. If you run a DOT R tire I would throw on a new set for each season and be done with it. We are running a very grippy Pirelli radial slick that delivers approx 1.5 lat g grip and it generates a fair amount of heat. Switching to an aluminum hat, floating rotor and larger cooling brake ducts dramatically lowered temps/potential of ABS fail. It's not so much the wheel "bearing" but the ABS module inside the hub. Cheap insurance at the beginning of the season if you run a fair amount of races.

Brake duct cooling backing plate from HRP: Yes it should work. If these are the carbon fiber ones send them back and buy the steel Mazdaspeeds. Probably much, much cheaper.

Setup: meyermotorsports@mac.com. Let me know your tire selection and I'll throw a baseline setup at you.

Fuel P sensor. At WOT these engines see 1,600F EGT. Fuel has a huge cooling effect and fuel starve = lean = toast. A smart racer like yourself will run the lightest amount of fuel possible and in doing so you are more prone to tank sloshing. Add to this a car that is purposefully setup with more grip and a talented driver and that ends up with a much higher potential of a little bit of leftover fuel sloshing around in the tank. SHOULD you get a fuel hiccup and your running WOT under high load uphill and high rpm----your motor is going to go boom or get hurt at the least. A Fuel P gauge into your AIM or other w an alarm will give you a heads up. Typically you'll get warning on that last corner prior to that long straight away. Lift, pull out, coast. We fried a couple of motors until we designed a super trick surge tank that takes all but about 8 oz out of the entire tank. Expensive but never failed. About $1,200 just in parts. Another benefit is that you can log your fuel p and figure out when/where it is skipping/dipping/etc. and do some root cause analysis. We USE to run the speedsource pump solution and we don't anymore. Get the idea?

Dump the trans. Run it anyway. That piece of **** will last two weekends if you baby it. Put a rental driver in it and it will last one weekend. We use to run two per car per weekend in Grand-Am. Cheat. This trans design is totally flawed. We would do serious repairs after each weekend. Always the 3/4 synchro. The 3/4 shift fork is the weak link and there is no fix. Trust me. Lobby to get the new trans or just run it. It is near bulletproof. The input shaft is about 50% smaller but the thing is like a rock. At one point I owned 7 pre-09 transmissions. The new one will pay for itself in one season PLUS you'll have to baby yours and I don't know about you-----do you baby stuff when your racing for or defending the lead?

Clutch/Fly: No they are a system. Take a look at my profile pics to see what I'm talking about. There is a shot of it on there.

Ron Davis: yes. If you are allowed underbelly tray mods I would seal the kraparoonie out of this and same for oil coolers. Remember, these engines have a symbiotic dynamic with their oil and water systems. Lowering one will help lower the other. Over cool both the oil and water and tape them up when you have to. We run our oil under 210F and water about 190 all day long. Usually have to tape up 1/2 of one of the oil coolers to do this. Same for the bottom of the nose. This gives you lots of options at Barber in August in the draft. A better fan on the backside of the rad is also less restrictive to air flow. The stock fans are just that. Check out a SPAL. Cost effective. Pulls like a freight train. Much less restrictive.

Diff cooler. Get one. We often see 300F in under a 1/2 hour. When our fan broke one time she ran 400 and I kept thinking the thing was going to lock up while running P2 at Toronto. Not a confidence inspiring type of feeling. The max temps a typical pump can see are around 230F sustained I believe. Pull fresh air from outside the car and it will lower your T about 25F.

Gotta boogie.

Eric

 

Looks like a run the same Tilton Clutch as you. My custom flywheel is not as heavily lightened however. In any case I found that I could still use the stock throw out bearing and arm with the Tilton Clutch - this simplifies expense and installation.

 

I need a little guidance/ feedback

I am not running any data Aquisition system this year... just not in my budget I did however install several guages and I am wondering what others are seeing as acceptable in racing conditions?

Trans Temp:
Diff Temp:
Oil Temp:
Water Temp:
Oil Pressure:
Fuel Pressure:


Thanks again for your continued help and support! We almost got to the point to start it up today but we are missing a "T" connection for the fuel test port. Next weekend I wont be working on it since it will be my first fathers day! So hopefully in two weeks I will have it running!

Stephen

PS: Eric I will e-mail you this week when I have a bit more time to put a thought out e-mail together!

 

Spent my day off yesterday working some more on the car! I had a new helper with me that enjoyed playing "keep away" The car is now looking like a real car for the first time in over a year and my wife actualy realizes that it really is a car! I think she had just figured it was some type of fancy money pit thing that sat in the garage, still trying to prove her wrong on that.

Stephen

 

You cant afford not to put Data Aquistition your budget even if it is not a Professional system, with GPS and OBD2 technology you can get a lot for a little. Add a video go pro video camara and you can have 90% of the professional system feautres for a fraction of the cost.

I use the racechrono Touch Screen Pro with OBD2 data logger. http://www.mh-motorsports.com/lap_timers.shtml

I have not actualy used the OBD2 datalogger yet (because I cant use my dahhawk at the same time) but you should be able to log your stock sensors (AFR, TPS, IAT, ECT, RPM) along side GPS speed, lap times, estimated g-force, split speeds and split times.

Car is looking good. My car is still a street car and watching a race car build makes me jealous. Good Luck.

 

The car is basically finished! I went up to the track and got a logbook this past weekend. I will be heading up to Watkins Glen to test on the 22nd then race that weekend in the www.ProItseries.com racing series! I doubt I will be that quick since it will be my first weekend really driving an RX8 but Iam excited to get a start and start sorting it for next season! I will be sure to post up some vidoes and pictures after our events if anyone is interested.

Below is a picture of me with my logbook! (taken with my phone) At some point I will post up some higher resolution pictures of the car finished.

Stephen

 

I like your car's number

 

Looks great! Best of luck!

 

Thanks guys! I can't wait to get it out on track and see what everyone here is bragging about... how well the RX8 handles

This site is a great resource and helped me learn a lot about these cars! I probably couldn't have built this thing without this site!

Stephen